38 



pair of feet is )epre.seiited by minute papillae. The caudal 

 stylets are veiv short, and furnished with three or four 

 short plumose setse at the apex. 



The external openings are the mouth, the YulviP, the 

 opening's of the vasa deferentia and the anus. 



The mouth is situated on the ventral surface of the 

 cephalo-thorax, at the apex of a conical tube, composed 

 of the upper and lower lips fused together. In the very 

 early cvclops stage the lips are not fused. The vulvse and 

 openings of the vasa deferentia are placed at the posterior 

 angles of the genital segment. The anus is at the apex of 

 the abdomen, in the middle line. The vulviB open into 

 the receptacula seminis, which are in direct coiumuni- 

 cation with the oviducts. 



The whole of the genital segment and abdomen in the 

 female is marked by fine transverse lines. The colour, 

 which is arranged in patches, varies from dark violet to 

 light red. 



Alimextary C.\xal. 



In the adult the mouth opens into the intestine, which 

 probably acts as the stomach, the CESophagus and true 

 stomach having disappeared in the metamorphosis of the 

 cephalo-thorax. The intestine is at first narrow Avhere 

 it passes through the neck, then it widens considerably in 

 the swollen part of the genital segment, contracting 

 slightly in the abdomen, and finally terminates in a short, 

 narrow rectum leading to the anus (Plate Y., fig. 4). 

 The intestine is lined with a single layer of nucleated 

 cells. Attached to this layer, and in some cases embedded 

 ill it at irregular intervals, are large cells filled with fine 

 granular material. In some parts these large cells are 

 grouped together two and three rows high. In other 

 l)arts they are quite free (Plate Y., figs. 5 and G). The 

 layer supporting the nucleated cells appears to be com- 



